Selected undergraduate research projects

Project #4: Philometroides bulbosus, a nematode parasite of the southern flounder

Project #3: Molecular mechanisms of heavy metal accumulation in acanthocephalans

Project #2: Population dynamics of a monogenean parasite of the striped mullet

Project #1: Sequencing of the CO1 gene of acanthocephalans

Philometroides bulbosus, a nematode parasite of the southern flounder: Claire Golléty – Marine Biology Major – Claire graduated in May 2004. She is pursuing her Ph.D. in marine ecology in France.

The philometrid nematode Philometroides bulbosus is a parasite of the southern flounder, Paralichthys lethostigma and we report it for the first time from South Carolina. A year long survey was performed to establish the presence and abundance of the parasite in our area. Our study focused on female worms, which are found encased in the buccal and gill cavities of the flounders. Results revealed the presence of P. bulbosus in 61% of the 109 flounders observed, throughout the year, and at all 10 sites surveyed in the South Carolina Estuarine system and off the coast. Another aspect of this study focuses on the nematode’s life cycle, which is unknown. Experiments are in progress to identify intermediate hosts of this parasite. This study is carried out in collaboration with the Inshore Fisheries Group at SC-DNR. Funded by the SC Sea Grant Consortium (NA 16 RG 2250) and the College of Charleston Summer Undergraduate Research program.

Article published: Golléty et al. Diseases of Aquatic Organisms (2005) vol. 65: 69-74.

Presentation by student:

2004. Population dynamics of Philometroides bulbosus, a philometrid nematode parasite of the southern flounder, Paralichthys lethostigma in South Carolina. Southeastern Society of Parasitologists Annual Meeting. Pigeon Forge TN. C. Golléty* ^Θ, V.A. Connors, W.A. Roumillat, and I. de Buron.

Population dynamics of a monogenean parasite of the striped mullet

The striped mullet, Mugil cephalus, is an abundant and commercially important fish found worldwide. M. cephalus harbors a variety of parasites, including the polyopisthocotylid monogenean, Metamicrocotyla macracantha on its gills. We studied for one year the population dynamics of this little-known worm because it had never been previously reported in the Charleston Estuarine System. Its presence in our area makes this the northernmost record of this species in the Atlantic Ocean and, thus, raises questions about its biology.  Results showed that M. macracantha is not found as often in low salinities (upper rivers) as in high salinities (Harbor, Cape Romain, etc) throughout the year, that mullet harbor more of them in winter months, and that this worm has a significant preference for the most distal gill arches on either side of the fish. These data enhance our understanding of the biology of both the monogenean and the striped mullet and raise questions related to the phylogeny of both the host and the parasite. This study was done in collaboration with the Inshore Fisheries group of SCDNR and was supported by the Department of Biology and the School of Science and Mathematics at the College of Charleston, and the SC-BRIN program.

Presentations by student:

2004: Co-occurrence of the copepod Naobranchia lizae, and the monogenean Metamicrocotyla macracantha on the striped mulletMugil cephalus. American Society of Parasitologists. Philadelphia PA. Poster presentation. T.G. Baker, E. Pante, W. A. Roumillat, E. Lesveque, and I. de Buron.

2003: Population dynamics of the polyopisthocotylid, Metamicrocotyla macracantha, a gill parasite of the striped mullet, Mugil cephalus in South Carolina. Southeastern Society of Parasitologists, Mobile AL T.G. Baker, W.A. Roumillat, and I. de Buron

2003: An ecological and morphological study of the monogenean, Metamicrocotyla macracantha, a gill parasite of the striped mullet, Mugil cephalus. South Carolina Academy of Science. Clemson SC. T.G. Baker, W.A. Roumillat, and I. de Buron.

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Sequencing of the CO1 gene of acanthocephalans: Eric Pante and Amelia Viricel – Marine Biology majors - Both have graduated in December 2002 and are now in the Marine Biology Graduate Program at the College of Charleston.

Acanthocephalans are parasitic worms with a complex life cycle that involves an arthropod intermediate host and a vertebrate definitive host. Very few genetic data are available for acanthocephalans and no work has been done on the mitochondrial cytochrome oxidase subunit I (CO1) gene of these worms. In collaboration with Dr. Scott France (Department of Biology, CofC) and with the help of his graduate students, we have sequenced part of the CO1 gene of 4 species of acanthocephalans and developed a molecular probe for the species Plagiorhynchus cylindraceus. This probe will be used to detect infection by this parasite in wild and experimentally infected populations of its isopod intermediate host, Armadillidium vulgare. We are planning on using this model in the teaching laboratory for students to learn the use of molecular tools in parasitology. Supported by the SC-BRIN program and a grant from the College of Charleston Center for Effective Teaching and Learning.

Molecular mechanisms of heavy metal accumulation in acanthocephalans: Elodie Rolando- Biochemistry major –This project was carried out in collaboration with Dr. Eric James from MUSC.

Acanthocephalans are intestinal worms found as adults in most vertebrates. Recently, some species of fish and mammal acanthocephalans were shown to accumulate heavy metals such as cadmium and lead at levels several fold higher than their hosts’ tissues and the exposure doses. To our knowledge, acanthocephalans are unique in that they appear to be extremely tolerant of these high concentrations of heavy metals. However, the molecular mechanism of such bioaccumulation of heavy metals by these worms is not known.

We hypothesized that similarly to what occurs in other organisms, acanthocephalans use an uptake mechanism involving carrier/transport proteins then a specific binding protein which allows the accumulation. In collaboration with Dr. Eric James from MUSC, we initiated a study to characterize these proteins by using the rat acanthocephalan, Moniliformis moniliformis as a model. The ultimate goal of this research is to understand the process(es) that prevent acanthocephalans from being affected by heavy metal accumulation. Identification of such process(es) would allow applications in bioremediation and in developing new methods concerning heavy metal therapy and detoxification. Funded by a BRIN grant ( 5P20RR16461-03) from the BRIN program of the National Center for Research Resources.